Opening another MGB GT engine can of worms

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I decided to hone the cylinders on both the 1967 MGB 18GB engine as well as the 1972 MGB 18V engine. The 18GB engine certainly needed this the most as there was a little glazing in a few areas and a very small ridge at the top of the piston bore that hopefully reaming will remove.

The 1972 18V engine cylinder bores didn’t look too bad but once again there was a very small ridge at the top of the bore. Regardless of what happens I decided that new rings couldn’t hurt so I ordered a set of .020 that will fit either engine. Here’s what the 18V cylinder bores looked like when I began.

MGB 18V engine cylinder bores
MGB 18V engine cylinder bores

I debated attempting to hone the cylinders with the crankshaft in place but decided this was too risky and it would only take perhaps half an hour to remove the crankshaft so that is what I did. This is where the can of worms comes in. Look at the main bearings below. Ughhhh!

MGB 18V crappy main bearings
MGB 18V crappy main bearings

I’m not sure if this crankshaft can just be polished or whether it will require a $200 regrind. One option I have is to use the older crankshaft that has already been reground and choose the best block for the build.

MGB 18V engine crankshaft with light scoring
MGB 18V engine crankshaft with light scoring

The 18V block cylinder bores honed nicely although I still may have a professional shop do it again. It almost seems a waste of time to completely rebuild an engine and not have it honed as well as possible. How does this look?

Newly honed 18V cylinder bore
Newly honed 18V cylinder bore

The 1967 18GB cylinder bores still have a very light ridge so perhaps need to be reamed. I could really use a new camshaft as well, but where does it all stop? I’m beginning to think that I should take all the best components and throw something together without spending more money. At a later date I can always build the additional block with some speed accessories for more oomph.

Honed MGB 18GB cylinder bores
Honed MGB 18GB cylinder bores

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